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951.
952.
953.
Translated from Steklo i Keramika, No. 1, pp. 11–12, January, 1992. 相似文献
954.
S. I. Gubenko 《Metal Science and Heat Treatment》1992,34(7):472-473
Conclusion In the matrix of the steels É3 and 08Kh18N10T close to nonmetallic inclusions under explosive treatment conditions, relaxation processes of the translational-rotational type occur. These are wavelike in character and lead to the formation of structures displaying complex deformation within the relaxation waves.Dnepropetrovsk Metallurgical Institute. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 7, pp. 32–33, July, 1992. 相似文献
955.
956.
R.I.R. Blyth S.S. Dhesi P.A. Gravil K. Newstead R. Cosso R.J. Cole A.J. Patchett T. Mitrelias N.P. Prince S.D. Barrett 《Journal of Alloys and Compounds》1992,180(1-2):259-263
Angle-resolved UV photoemission has been used to investigate the electronic structure of the (0001) surfaces of scandium, yttrium, praseodymium and gadolinium. Off-normal emission spectra were recorded with high angular resolution, enabling detailed mapping of the dispersion of valence band features. Yttrium and gadolinium show similar results to published data from Ho(0001), suggesting minimal 4f influence in the lanthanide bandstructures. Differences seen on praseodymium and scandium may be due to 4f derived states and surface states respectively. 相似文献
957.
Comparison of six methylation methods for analysis of the fatty acid composition of albacore lipid 总被引:2,自引:0,他引:2
I. MEDINA S. AUBOURG J. M. GALLARDO R. PÉREZ-MARTÍN 《International Journal of Food Science & Technology》1992,27(5):597-601
Six methods widely used to produce methyl esters for the gas chromatographic determination of the fatty acid composition of a marine lipid were compared. Four acid-catalyzed methods (1% H2 SO4 : CH3 OH; 5% HCl: CH3 OH; 7% and 14% BF3 : CH3 OH) and two base-catalyzed methods [0.5M NaOCH3 : CH3 OH; (1:4) tetramethylguanidine: CH3 OH] were used.
The use of BF3 : CH3 OH (7% and 14%) gave a lower content of 18:1 n9 than the other methods and produced an artefact (2.7–3.2% of total fatty acid content) eluting between the 20:5 and 24:1 fatty acid methyl esters. No significant differences were obtained between the other four methods.
Accordingly the use of BF3 : CH3 OH for transmethylation of marine lipids is not recommended. Results obtained in the other four methods showed that all are comparable. 相似文献
The use of BF
Accordingly the use of BF
958.
959.
DM Haig A Percival J Mitchell I Green D Sargan 《Canadian Metallurgical Quarterly》1995,45(3-4):221-236
An in vitro culture system is described which allows an analysis of the signals responsible for the survival, growth and functional maturation of afferent lymph dendritic cells (ALDC), a subpopulation of migrating dermal dendritic cells involved in antigen carriage and presentation to T-cells. Purified ALDC survived and grew for up to 30 days in lymph node conditioned medium and survived 14 days in recombinant ovine (rov) TNF-alpha whereas none were detected after 24 h in rov GM-CSF, rov IFN-gamma or rh M-CSF. However, when rov GM-CSF was added to cultures along with rov TNF-alpha, increased numbers of ALDC compared with input numbers (growth) were recorded on Days 14 and 21. In contrast, when 50-200 units ml-1 of rov IFN-gamma were added to cultures of ALDC along with TNF-alpha or rov TNF-alpha plus rov GM-CSF, cell survival and growth was inhibited. Antibody blocking studies confirmed the cytokine specificity of these effects. ALDC cultured in rov TNF-alpha or rov TNF-alpha plus rov GM-CSF retained MHC Class-II and ov CD-1 antigen expression and accessory function for autologous ov CD-4 T-cell proliferation, although at reduced levels compared with freshly isolated cells. Neither fresh nor cultured ALDC expressed coagulation factor XIIIa. 相似文献
960.